Raise minor version to 2.11.0

- `master` then targets `2.11.0`
- development version will properly order WRT `2.10.0`, being `2.11.0.dev.b<git branch hash>.<ci provider><ci monotonic id>.g<git short sha>`
- system tests will be able to target `master` without conflicting with released `2.10.0`

lib/datadog/version.rb

@@ -3,7 +3,7 @@
 module Datadog
   module VERSION
     MAJOR = 2
-    MINOR = 10
+    MINOR = 11
     PATCH = 0
     PRE = nil
     BUILD = nil